The sad thing is that on the other fora he had a valid point; but got hung up on another issue.
The problem is stating things as fact when they are opinion and not allowing other opinions.

Like - beginners must shoot JPEG ...
well I agree in the very early learning process, but as soon the the beginner has a handle on composition, exposure and depth of field there is no reason to stay with JPEG.
As soon as a beginner can get into processing raw they will grasp what used to happen in a dark room and they will learn quickly.